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I have a 1986 Jeep Grand Wagoneer with a blown engine. I've been looking for a donor to replace it and came across the 4BT idea.

I have zero technical knowledge. I can't do the work myself. Can't even help. When it comes to getting this done - sourcing the parts, making decisions, etc., is it going to be worth trying?

Don't know where to look for an engine, if I should buy new or used, what kind of transmission to get, how to go about any of it. I just love the idea of it. I mean, hell, I only got 6 MPG with the original engine. Would love the improvement.

Any input would be much appreciated.
 

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What is wrong with your gasser? I would fix it or find a running donor so you can drive your vehicle. If you cannot do the work or at least line up the parts beforehand, it probably will cost way more than you wish to afford.

Then, hang out here and learn the ins and outs of switching to diesel.

Ed in CO.
 

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I think one of the pistons threw a rod.

I was looking for a donor but the main problem I'm having is that I live in California and finding something with the smog equipment I need is not easy. The engine I was running wasn't compliant and I was in the middle of trying to fix that problem already.
 

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I have a 1986 Jeep Grand Wagoneer with a blown engine. I've been looking for a donor to replace it and came across the 4BT idea.
I have zero technical knowledge. I can't do the work myself. Can't even help. When it comes to getting this done - sourcing the parts, making decisions, etc., is it going to be worth trying?
Don't know where to look for an engine, if I should buy new or used, what kind of transmission to get, how to go about any of it. I just love the idea of it. I mean, hell, I only got 6 MPG with the original engine. Would love the improvement.
Any input would be much appreciated.
I think your most cost effective solution is to replace/repair the blown engine and add a after market fuel injection. But the engine should be a AMC 360 and I"m not sure of the bolt patten for the 727 torque flite trans and the engine. More than likely the 360 bolt pattern is proprietary to AMC so attaching a late model Chrysler engine would probably not happen.
Any way for the 4B swap the going price for a complete running 4BT is about $3000 to $5000. Then you have to mate it to a "Diesel" rated transmission. The 727 in your Wagoneer will not work. And it gets more costly the farther you go.
You might try international full size jeeps association for some insight on the engine.
I have a 89 Wagoneer thats going under the wrench for a 4BT swap in a few months, from my research the 4BT swap into a Woneneer is a relative easy swap.
 

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.... The engine I was running wasn't compliant and I was in the middle of trying to fix that problem already.
If you need to be emissions compliant in California, I don't think that swapping in a diesel engine will pass emissions. Lots of California specific knowledge needed. You will need to master the ins and outs of the engine swapping rules - and advice from out of CA does not apply to CA.

A quick Google search shows that the California cutoff year for emissions testing is 1975. If your heart is set on building a diesel vehicle, start with an older vehicle to avoid emissions testing. You still need to build wisely, because "rolling coal" in CA will get you the kind of attention that you do not want...

As scout4bta suggested, sourcing an AMC engine of the correct year is the most straight forward solution - a 34 year old engine might be hard to find and rebuild to emissions standards - and find all the required emission parts.

The bellhousing bolt pattern is specific to AMC.

Maybe just buy a vehicle that currently passes CA emissions to keep you on the road and slowly learn about diesel conversions. As a general rule, the newer fuel injection engines get better fuel mileage that the older carbureted engines.

VW TDI diesel if you want a diesel.

Read my 1986 Ford build in the link below. It is one of the simple swaps here. My first diesel swap, but, not my first engine swap. It took me months to get on the road.
 

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Your situation is sort of like being caught between the the rock and the hard place. From my understanding even if you rebuild your original engine there will be mods required to make it smog compliant. Wonder if that's even possible for a 34 year old vehicle. Need to check with the local DMV to see what possible courses you might have. A 4bt probably won't meet regulations. Here in NC they stop inspecting vehicles at 30 years. Found that out when I went for the inspection and the person said it was no longer needed on my vehicle which is 1990. California is a different world. We have several members in your state and maybe one of them can give some insight. The only Cummins diesel that I know would meet any state regulations is the new R2.8. It's certified 50 state legal. It's not cheap. The diesel from a late model Toyota Tacoma might be a possible but might be hard to find. They discontinued it for the 2020 model.
 

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Personally I would find a shop to swap a 5.3l/4l60 from a 99-2006 Chevy truck/ suburban. Would be the cheapest / easiest swap.
I have a 1989 grand wagoneer with a 6bt
 

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If you need to be emissions compliant in California, I don't think that swapping in a diesel engine will pass emissions. Lots of California specific knowledge needed. You will need to master the ins and outs of the engine swapping rules - and advice from out of CA does not apply to CA.

A quick Google search shows that the California cutoff year for emissions testing is 1975. If your heart is set on building a diesel vehicle, start with an older vehicle to avoid emissions testing. You still need to build wisely, because "rolling coal" in CA will get you the kind of attention that you do not want...

As scout4bta suggested, sourcing an AMC engine of the correct year is the most straight forward solution - a 34 year old engine might be hard to find and rebuild to emissions standards - and find all the required emission parts.

The bellhousing bolt pattern is specific to AMC.

Maybe just buy a vehicle that currently passes CA emissions to keep you on the road and slowly learn about diesel conversions. As a general rule, the newer fuel injection engines get better fuel mileage that the older carbureted engines.

VW TDI diesel if you want a diesel.

Read my 1986 Ford build in the link below. It is one of the simple swaps here. My first diesel swap, but, not my first engine swap. It took me months to get on the road.
Wow, thanks for the info. Does seem like from a practical standpoint sticking with gas is the way to go. Tho here in california, we don't have to smog Diesels older than 1997. I have a 1980 Diesel FJ40 and it's exempt.

I also don't think I can go months on a diesel swap project :)
 

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It all depends on what you want, and how bad you want it. The swap you're talking about, is hugely labor intensive, and requires literally thousands of dollars in parts. Most mechanics would not even be interested in attempting this. This is a project for someone with a love for diesels and/or someone who loves a challenge. This isn't something that will be done in a day or 2, or even a week or 2. I don't mean to discourage anyone concerning something they are really wanting to do, but I would suggest you explore other options. If you're set on keeping the Wagoneer, I would just find a replacement gas engine, and have it swapped out. If you are set on putting a diesel in it, it's going to take lots of money and time, and it might be a challenge to find a competent mechanic that's willing to take on a project like that. Whatever you decide, best of luck to you!
 

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Does that transmission work for a 4wd?
yes, it will have a 4l60e tranmssion and transfer case with the right driveshaft orientation. It’s not a bolt in but a much much more popular easy swap.

getting a vehicle that was originally gas, registered as a diesel is not easy In California. The Diesel needs to be from the same weight class vehicle. Same year or newer and still retain all emmsions items.
a 4bt never came in a 1/2 ton vehicle.

if diesel Is the way you want to go you can run a gm 6.2l/6.5l. some may steer you away from these but I like them.
I got very lucky when registering my 6bt wagoneer. Kind of got In under the radar
 

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I have a 1986 Jeep Grand Wagoneer with a blown engine. I've been looking for a donor to replace it and came across the 4BT idea.

I have zero technical knowledge. I can't do the work myself. Can't even help. When it comes to getting this done - sourcing the parts, making decisions, etc., is it going to be worth trying?

Don't know where to look for an engine, if I should buy new or used, what kind of transmission to get, how to go about any of it. I just love the idea of it. I mean, hell, I only got 6 MPG with the original engine. Would love the improvement.

Any input would be much appreciated.
Get rid of it ,that AMC 360 sucks I have a a 4 bta in my 1984 grand wagoner nv 4500 np 241 LOVE IT
 

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yes, it will have a 4l60e tranmssion and transfer case with the right driveshaft orientation. It’s not a bolt in but a much much more popular easy swap.

getting a vehicle that was originally gas, registered as a diesel is not easy In California. The Diesel needs to be from the same weight class vehicle. Same year or newer and still retain all emmsions items.
a 4bt never came in a 1/2 ton vehicle.

if diesel Is the way you want to go you can run a gm 6.2l/6.5l. some may steer you away from these but I like them.
I got very lucky when registering my 6bt wagoneer. Kind of got In under the radar
Just stay away from the GM diesel that is a gas converted to diesel , according to a diesel mechanic I new in Ca they are NO GOOD !
 

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Your situation is sort of like being caught between the the rock and the hard place. From my understanding even if you rebuild your original engine there will be mods required to make it smog compliant. Wonder if that's even possible for a 34 year old vehicle. Need to check with the local DMV to see what possible courses you might have. A 4bt probably won't meet regulations. Here in NC they stop inspecting vehicles at 30 years. Found that out when I went for the inspection and the person said it was no longer needed on my vehicle which is 1990. California is a different world. We have several members in your state and maybe one of them can give some insight. The only Cummins diesel that I know would meet any state regulations is the new R2.8. It's certified 50 state legal. It's not cheap. The diesel from a late model Toyota Tacoma might be a possible but might be hard to find. They discontinued it for the 2020 model.
in calif they did not start smoging diesel till 1998. All you need is to fill out a statement of facts. And take it to dmv for a look see. In2012 I brought a 98 wrangler with the throught of a 4bt conversion. Talked to the referee about it and he said no way. You could not put 3/4 ton engine in a 1/2 ton vehicle when I asked him about 97 and earlier years he said that was dmvs problem. So I brought a 97 wrangler did the conversion and took it to Arvin dmv and the inspector spent more time looking at my seat belts than the engine. I had no trouble getting it passed. If you go to dmv site and look up engine change it will give u all the info you need. Good luck. Hoped this helped
 

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ive done many here in cal, and have a '63 j200 converted, went from 11 - 19 mpgs, for the swap, motor must be same year or newer, take vehicle to referee, they will issue exemption status to vehicle on 1998 and earlier engines, as mentioned previously, the engines were replaced by fleet cummins, replacing gassers, in bread and chip delivery trucks, i bought 13 from interstate brands here in cal, all registrations were to be terminated by dmv, not in compliance with c.a.r.b. emissions standards, every one i harvested is driving exempt here on california roadways, so much for deleting these from registration status. the shorter 4bt is same lenght as sb v8, and simple conversion, cummins sales pitch was double your fuel economy, reduce maintenance in less than half, go 5 times farther.
 

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If you need to be emissions compliant in California, I don't think that swapping in a diesel engine will pass emissions. Lots of California specific knowledge needed. You will need to master the ins and outs of the engine swapping rules - and advice from out of CA does not apply to CA.

A quick Google search shows that the California cutoff year for emissions testing is 1975. If your heart is set on building a diesel vehicle, start with an older vehicle to avoid emissions testing. You still need to build wisely, because "rolling coal" in CA will get you the kind of attention that you do not want...

As scout4bta suggested, sourcing an AMC engine of the correct year is the most straight forward solution - a 34 year old engine might be hard to find and rebuild to emissions standards - and find all the required emission parts.

The bellhousing bolt pattern is specific to AMC.

Maybe just buy a vehicle that currently passes CA emissions to keep you on the road and slowly learn about diesel conversions. As a general rule, the newer fuel injection engines get better fuel mileage that the older carbureted engines.

VW TDI diesel if you want a diesel.

Read my 1986 Ford build in the link below. It is one of the simple swaps here. My first diesel swap, but, not my first engine swap. It took me months to get on the road.

You are correct about the cutoff year for smog exemption. After that, a diesel swap must be compliant to the equipment that was required for a vehicle of the year on the title. So if you put in a 4bt in your 86, you will need the smog equipment required for a 4bt sold in 86. (which I believe was nothing.) The CARB folks will go out of their way to discourage a diesel conversion, but once you have it done and meet the letter of the law, they will register it. Whatever diesel you choose, it must be one that was certified for sale sOmewhere in the US at sometime, and smog equipment to match the year that is on the title of the car. (So the 3 liter toyota diesel will never register in CA)

It will not be cheap! There are several driving advantages for diesel in an off-road rig. Fuel economy, increased low-end torque (at awesome levels!) are some starters. You will also have a lot more noise and vibration with a 4bt. It will cost somewhere around three times as much as rebuilding the 360 gasser. The VW TDI suggestion was the choice I made for my 62 Willys truck. I found a 98 Jetta as donor and stripped out everything I could think of to use in the build, which is currently at about the halfway mark. I am also doing a frame swap so it has taken over a year to get this far in my spare time. The TDI swap will need a special adaptor and starter to mate it up to the AMC transmission. I am building my own, but there is one available from KotyBuilt for around $1500. The VW motor will be a significant power decrease from the 360, which will be an impact on the drive experience and your expected mileage. Review engine specs carefully before you choose.
 

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If you pay someone with a good reputation to do the swap it is highly unlikely that you will ever recover money spent in reduced fuel consumption or resale. Even doing a swap yourself it's possible to get upside down. Drive a 4bt powered rig before you go the 4bt route. Swapped vehicles aren't favored amongst the average mechanic, some repair shops won't touch them. It's almost imperative to be somewhat mechanical if you drive a swapped rig unless you get something like a 2.8 and pay big bucks for a turn key swap.
 

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Have to agree, most cost effective solution to getting it on the road is repair or replace existing engine. I’ll bet an internet search reveals a fair amount of potential used engines.

Having done several engine swaps within make, and swapping gas to diesel, it sure is tough if you can’t do some work yourself.
 
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